2010—2012年青岛海滨浴场67周次浮游植物的群集特征          下载免费PDF全文

林虓  尤凯  毛霞  张秀梅 《海洋科学进展》2015,33(1)

2010—2012年对青岛汇泉湾海滨浴场区2站点的浮游植物及环境因子进行67周次连续监测,共检出浮游植物53属94种,细胞总丰度的变化范围为7.19~272.35个/mL,均值为46.74个/mL,硅藻在细胞总丰度中的比例平均达70.34%,主要优势种有骨条藻、角毛藻、菱形藻、新月筒柱藻和舟形藻。调查期内,共检到3次硅藻的赤潮,未检到营养盐发生限制的现象。周年的统计分析显示,调查区浮游植物群落中的羽纹硅藻类与营养盐呈显著的相关关系(P0.05)。在浴场开放期,Chl-a质量浓度均值达7.26mg/L,为全年最高,浮游植物群落以羽纹硅藻类最占优势,并且Chl-a与羽纹硅藻丰度呈现极显著的正相关(P0.01)。特别对羽纹硅藻在开放期占优势可能引发的不利影响作了探讨,并建议在今后监测和评价该类休闲水域时,应对此给予重视。  相似文献   

突变模型势函数的一般表示式及用于富营养化评价   总被引：5，自引：0，他引：5       下载免费PDF全文

李祚泳  郭淳  汪嘉杨  李燕 《水科学进展》2010,21(1):101-106

通常的初等突变评价模型仅给出控制变量维数n≤4的突变模型的势函数及相应的归一化公式,对高维(n≥5)的复杂系统需将其分解为若干维数小于4的多层子系统后再递归进行,且一般只给出各评价结果的相对排序.通过对初等突变模型势函数形式和相应的归一化公式的观察、比较和分析归纳,推演出包括任意维的突变模型的势函数形式及其相应的归一化公式.将推导出的突变评价归一化公式和分层递阶降维突变评价模型相结合,实现对指标众多的复杂系统的评价和分类.将突变评价公式应用于北京市21个湖泊的富营养化评价,并与多种评价方法进行了比较.结果表明,除1个湖泊的评价结果有相邻一级之差外,其余20个湖泊的评价结果完全一致,表明推演出的高维突变势函数形式和归一化公式是合理的.将其用于湖泊富营养化评价具有简单、实用的特点.  相似文献   

Comparison between epiphyte assemblages of leaves and rhizomes of the seagrass Posidonia oceanica subjected to different levels of anthropogenic eutrophication     

David Balata  Iacopo Bertocci  Luigi Piazzi  Ugo Nesti 《Estuarine, Coastal and Shelf Science》2008,79(3):533-540

This paper aimed to compare epiphyte assemblages of leaves and rhizomes of Posidonia oceanica exposed to different levels of concentration of nutrients. The same design including a potentially impacted meadow and two reference meadows was used in each of two locations, characterized by the presence of a city or of suspended cages of a fish farm, respectively. This allowed to test for the consistency of responses of epiphytic assemblages to different sources of eutrophication. In both studies, results documented differences in patterns of composition and abundance of epiphytic assemblages on leaves between disturbed and reference meadows, while assemblages on rhizomes did not appear sensitive to this kind of disturbance. Moreover, in potentially impacted meadows, both assemblages showed different patterns of spatial variability compared to reference assemblages. Species composition and abundance of epiphyte assemblages seemed suitable for detecting moderate nutrient increases, even if adequate sampling designs are needed to separate patterns related to the large natural spatial variability of these systems from those related to changes in environmental conditions.  相似文献   

Chrysophyte cysts as paleolimnological indicators of environmental change due to cottage development and acidic deposition in the Muskoka-Haliburton region, Ontario, Canada     

Anna N. Wilkinson  Roland I. Hall  John P. Smol 《Journal of Paleolimnology》1999,22(1):17-39

Chrysophyte cysts preserved in recent and pre-industrial lake sediment samples from 54 Muskoka-Haliburton (Ontario) lakes were used in a paleolimnological study to determine the impact of acidic precipitation and cottage development on water quality. A total of 246 cyst morphotypes were identified. Ecological preferences of cyst morphotypes were determined using multivariate statistical analysis, cluster analysis, and species-environment correlations. Recent cyst assemblages were related to water chemistry and lake morphometric variables using Redundancy Analysis (RDA). The distribution of morphotypes was related to a gradient of acid neutralising capacity (ANC), expressed through the association of variables related to buffering (i.e. longitude, watershed area, and ionic concentration) with the first axis (₁ = 0.29). Cyst assemblages were also defined, to a lesser extent (₂ = 0.06), by a trophic status gradient, created through the combination of total nitrogen (TN), total phosphorus (TP), volume-weighted cottage density, and lake depth variables. The identification of lakewater pH and trophic status as important determinants of cyst assemblage structure allowed for the reconstruction of acidification and eutrophication related water chemistry changes using fossil cyst assemblages. The reconstruction of pre-industrial (pre-1850) water quality conditions with fossil cyst assemblages indicated that pH significantly decreased in 24.1% of the study lakes and increased in 16.7% of the lakes. Increases in pH in more alkaline drainage basins are attributed to alkalinity generation processes induced by acidic precipitation as has been shown in other studies. Total phosphorus (TP) concentrations significantly declined in 12.9% of the lakes and increased in 16.6% of lakes. Increases in [TP] were linked to cottage development. Decreases in trophic status may be due to landuse changes, the result of the acidification occurring in the area, or warmer and drier climates. A comparison of chrysophyte cyst and diatom water quality inferences show similar trends in pH changes. There is a good agreement between diatom and chrysophyte bioindicators with respect to [TP] changes in oligotrophic lakes (< 10 g/L); however, diatom inferences suggest that lakes with current [TP] values greater than 10 g/L have decreased in trophic status over time, while chrysophyte reconstructions suggest that these same lakes have become more productive systems.  相似文献   

基于集对分析和模糊集合论的水体营养化评价模型的应用研究   总被引：15，自引：0，他引：15  

王栋朱元姓  赵克勤 《水文》2004,24(3):9-13,41

尝试在水环境评价领域引入并应用集对分析和模糊集合论，结合水体营养化等水环境评价中模式识别、等级评价问题的实际应用，将相关的概念和理论进行拓广，定义了广义联系熵和广义相对隶属度。分别建立了基于集对分析的水体营养化评价一级模型和基于集对分析一模糊集合论的水体营养化评价二级模型。我国12个有代表性的湖库营养化程度评价的应用实例表明：所建模型的评价结果与调查结果相符，与单一模糊模式识别结果基本相符；二级模型与一级模型和单一模糊模式相比，评价结果相对全面，更符合用水障碍调查结果的实际情况；而且从广义联系熵判断，二级模型的广义联系熵较一级模型和单一模糊模式大一些，即更好地反映了待评价水样与评价标准两个集合的确定不确定关系和联系程度，从而在一定程度上验证了所建模型的有效性和简便性。文中所用理论方法和所建模型也可推广应用于其他领域。  相似文献   

乌梁素海富营养化主控因子年季变化分析及综合评价   总被引：19，自引：0，他引：19  

李畅游刘廷玺  高瑞忠任春涛 《水文》2004,24(3):14-17,24

运用均匀随机数以等级评价标准产生建模样本和验证样本，利用实数编码的加速遗传算法(RAGA)求解逻辑斯缔曲线(Logistic Curve)水环境评价模型中的参数，建立了富营养化等级评价模型，据此计算了乌梁素海1996∽2003年夏初、仲夏、秋末3个时点的富营养化等级，分析了乌梁素海富营养化主控因子及其等级的年季动态变化特征和它们之间的影响关系。结果表明：1996∽2003年乌梁素海各富营养化主控因子均变化在4级富营养化指标左右，除总磷波动性较大以外，其他各项指标均呈逐年恶化趋势；而综合富营养化等级均超过4级，且呈逐年增加趋势，目前已十分接近5级——极富营养化状态。  相似文献   

Vertical distribution of phosphorus and P-dissolving/decomposing bacteria in the sediment of Guanting reservoir     

LI Cui  YUAN Hongli  HUANG Huaizeng 《中国科学D辑(英文版)》2005,48(Z2)

In this study, we determined pH, phosphorus content and the number of P-dis- solving/decomposing bacteria in relation to the depth in the sediment of Guanting reservoir in Beijing. The pH value was slightly increased from 8.0 in the surface to 8.5 in the bottle (69 cm in depth) of sediment. The highest P content, 1269 mg/kg, was detected in the 35 cm layer, followed by the 5 cm (993 mg/kg) and 69 cm (580 mg/kg) layers. The number of inorganic P-dissolving bacteria varied from 6(102 to 8(104 and the organic P-discomposing bacteria were from 1.9(103 to 6.3(104 per gram sediment in different depths, which were counted under 28℃ and 20℃ ( pH7.5 and 8.5. The number of P-dissolving/discomposing bacteria was directly correlated to the P content in each layer of sediments. The analysis of P-dissolving/decomposing ability of bacteria showed that some of these bacteria were also capable of accumulating P intracellularly. The intracellular P-accumulation was more efficient at lower temperature; in contrast, the activity of P-dissolving/decomposing was stronger at higher temperature. So the content of dissolved P in water body, or quality of water, could be affected by the change of temperature via the regulation of bacterial activity. On the basis of 16S rDNA sequencing, the 13 efficient P-dis- solving/decomposing bacteria were identified as Bacillus spp., Bacterium sp., Microbacterium sp., Paenibacillus sp. and Pseudomonas sp.  相似文献   

物理及生物技术在密云水库富营养化防治中的应用   总被引：5，自引：0，他引：5  

董悦安  孟庆义  顾华  张景峰  高云柱 《地学前缘》2005,12(Z1):77-82

为防治密云水库富营养化问题,应用部分物理和生物技术进行现场试验。吸附性材料净水试验后,试验区内水中氮的浓度和磷的浓度比对照区都有所下降,这将对藻类生长所需的营养物质量起到一定的控制作用。水葫芦净化水体试验说明,试验区内水体的总磷和总氮浓度皆低于对照水体的,这将控制藻类生长所需的营养物质量,即控制藻类的生长速度。机械除藻试验后,水中的叶绿素含量比除藻前下降60%~100%。表底层水体交换试验后,试验区内表、中层水体的温度有所下降,温度降低将抑制表、中层水体中藻细胞的繁殖速率,对水华的发生将起到一定的抑制作用。  相似文献   

双目标耦合不确定性模糊模式识别模型   总被引：3，自引：0，他引：3  

高永胜  王淑英  丁春梅 《水文》2006,26(1):34-37

本文在陈守煜建立的模糊模式识别理论的构架基础上,将加权广义距离与模糊熵最小作为模式识别的复合目标函数,建立了考虑随机和模糊不确定性,使目标函数最小的新型模糊模式识别耦合模型。应用此模型对我国12个湖库的富营养化程度进行综合评价,并与原模型的双目标结果进行比较,说明本文建立的模型考虑了不确定性因素的优越性。  相似文献   

Eutrophication study at the Panjiakou-Daheiting Reservoir system, northern Hebei Province, People＇s Republic of China： Chlorophyll-a model and external and internal sources of phosphorus and nitrogen     

Joseph Domagalski Chao LIN Yang LUO Jie KANG Larry Brown Mark Munn 《中国地球化学学报》2006,25(B08):136-137

Concentrations and loads of nitrate and total phosphorus and the sources of these two nutrients were investigated at the Panjiakou and Daheiting Reservoir system in northern Hebei Province, the People＇s Republic of China. The Luanhe River is the primary source of water to these reservoirs. The response of the reservoir system from the phosphorus loading, with respect to chlorophyll-a production from algae, was fitted to a model of normalized phosphorus loading which regresses the average summer-time chlorophyll-a concentration to the average annual phosphorus concentration of the reservoir. The reservoirs have a primary use for drinking water and partially supplies the city of Tianjin with its annual supply, but secondary uses include flood control and aqua culture （fish cages）. Comparison of the normalized phosphorus loading and chlorophyll-a response of this system to other reservoirs throughout the world from similar studies indicates an elevated level of eutrophication, which will require an approximate 10-fold decrease in phosphorus load reduction to bring the system to a more acceptable level of algal productivity. Isotopes of nitrogen and oxygen in dissolved nitrate were measured from the headwater streams and at various locations along the major river system that provides the majority of water to this reservoir, and within the two reservoirs.  相似文献